This invention relates to a portable collapsible domestic cart and more particularly to a collapsible cart which may be utilized for food service. It is often desired in the home, and in many commercial establishments, to have a food service cart which can readily support plates or trays of food and which can be conveniently rolled from one location to another to facilitate the serving of food. It is also desirable that such food service carts, particularly when used in the home, be collapsible to a small size for easy and convenient storage when the cart is not in use.
Collapsible carts have been provided heretofore, and in particular collapsible carts intended for food service. Illustrative of some of these prior collapsible carts are those disclosed is U.S. Pat. No. 4,740,010 to Moskovitz, U.S. Pat. No. 5,730,452 to Fields, U.S. Pat. No. 3,436,092 to Werner and U.S. Pat. No. 3,074,734 to Munsen et al. Each of these patents disclose and describe collapsible and foldable carts applicable for food service.
U.S. Pat. No. 4,740,010 to Moskovitz discloses a foldable cart wherein a plurality of vertically spaced tray members are pivoted at their outer ends to end frames and pivotally mounted at their inner ends to a lift bar member. A mechanical stop is provided to secure the cart in both the fully opened and fully closed position. The lift bar mechanism employed results in increasing the height of the cart when it is in its folded position so that an increased height storage facility is necessary. U.S. Pat. No. 3,436,092 to Werner discloses a collapsible cart where a pair of upper and lower tray members are pivotally mounted to end support members and move from a vertical position to a horizontal position when the cart goes from its collapsed position to its open position. U.S. Pat. No. 5,730,452 to Fields discloses a collapsible cart where a plurality of tray members are pivotally mounted along their mid-point to side frame members which are hinged so as to move from an opened position to a closed position in an accordion fashion. U.S. Pat. No. 3,074,734 to Munsen et al.discloses a collapsible serving cart where the tray support members are pivotally mounted toward the rear to a frame member and move from a collapsed position where the tray members are vertically disposed to an open position with the tray members are horizontally oriented.
The present invention provides a collapsible food domestic cart that is movable between an expanded open and a collapsed storage position. Preferably, the collapsible cart comprises a central structure that includes a pair of upright centrally located support members at each side of the cart. The support members may also include upper and lower relatively short fixed horizontal panels. Each central support member serves as an anchor for one end of a lazy-tong type mechanism on either side of the support members. Upper and lower support trays are pivotally connected to the upper and lower horizontal panels so that the trays can pivot from a collapsed position to an open service condition. The collapsible trays are also supported by moveable legs at each of the four corners of the cart which form an outer support frame for the trays. The bottom of each leg is equipped with a wheel so that the cart, either in its open or closed state, can be readily wheeled from place to place. The lazy-tong collapsing mechanism provides that the cart collapses in essentially a parallel manner so that there is no increase in the height of the cart between its open and collapsed state.
To accommodate the collapsible movement of the cart, each of the central support members are equipped with a compression spring in its lower end. The springs are in the fully compressed position when the cart is expanded into its operable mode, and in a neutral position in the collapsed position. The compression springs assist in helping movement when the cart is moved from the open to its collapsed storage position. This facilitates closure of the collapsible food domestic cart.
The underside of each collapsible tray segment also carries a block member having a notch therein which receives the end of a guide strip rib. When the cart is opened, the guide strip slides along a lateral support member until the end of the guide strip engages a groove in the block member mounted to the underside of each tray.
It is an object of the present invention to provide a collapsible cart assembly suitable for food service which expands from a collapsed condition where one or more tray members are in a substantially vertical position to an open service condition where there is no substantial increase in the vertical height of the assembly between the open service and collapsed condition.
It is a further object of the present invention to provide a collapsible domestic cart wherein one or more tray members are pivotally supported on a support member at one end and. supported by a frame support at the other end and wherein the frame support is connected to the support member by an articulating mechanism which moves the frame support relative to the support member without a substantial overall increase in the vertical height of the domestic cart.
A further object of the present invention is to provide a collapsible domestic cart which can be reliably and easily opened and collapsed without undue effort.